Identifying genetic susceptibility to Aspergillus fumigatus infection using collaborative cross mice and RNA-Seq approach

Background:Aspergillus fumigatus(Af)is one of the most ubiquitous fungi and its infection potency is suggested to be strongly controlled by the host genetic back-ground.The aim of this study was to search for candidate genes associated with host susceptibility to Aspergillus fumigatus(Af)using an RNAseq approach in CC lines and hepatic gene expression.Methods:We studied 31 male mice from 25 CC lines at 8 weeks old;the mice were infected with Af.Liver tissues were extracted from these mice 5 days post-infection,and next-generation RNA-sequencing(RNAseq)was performed.The GENE-E analysis platform was used to generate a clustered heat map matrix.Results:Significant variation in body weight changes between CC lines was ob-served.Hepatic gene expression revealed 12 top prioritized candidate genes differ-entially expressed in resistant versus susceptible mice based on body weight changes.Interestingly,three candidate genes are located within genomic intervals of the previ-ously mapped quantitative trait loci(QTL),including Gm16270 and Stox1 on chromo-some 10 and Gm11033 on chromosome 8.Conclusions:Our findings emphasize the CC mouse model's power in fine mapping the genetic components underlying susceptibility towards Af.As a next step,eQTL analysis will be performed for our RNA-Seq data.Suggested candidate genes from our study will be further assessed with a human cohort with aspergillosis.

Skeletal phenotypes and molecular mechanisms in aging mice

Aging is an inevitable physiological process,often accompanied by age-related bone loss and subsequent bone-related diseases that pose serious health risks.Research on skeletal diseases caused by aging in humans is challenging due to lengthy study durations,difficulties in sampling,regional variability,and substantial investment.Consequently,mice are preferred for such studies due to their similar motor system structure and function to humans,ease of handling and care,low cost,and short generation time.In this review,we present a comprehensive overview of the characteristics,limitations,applicability,bone phenotypes,and treatment methods in naturally aging mice and prematurely aging mouse models(including SAMP6,POLG mutant,LMNA,SIRT6,ZMPSTE24,TFAM,ERCC1,WERNER,and KL/KL-deficient mice).We also summarize the molecular mechanisms of these aging mouse models,including cellular DNA damage response,senescence-related secretory phenotype,telomere shortening,oxidative stress,bone marrow mesenchymal stem cell(BMSC)abnormalities,and mitochondrial dysfunction.Overall,this review aims to enhance our understanding of the pathogenesis of aging-related bone diseases.

AAV mediated carboxyl terminus of Hsp70 interacting protein overexpression mitigates the cognitive and pathological phenotypes of APP/PS1 mice

The E3 ubiquitin ligase,carboxyl terminus of heat shock protein 70(Hsp70)interacting protein(CHIP),also functions as a co-chaperone and plays a crucial role in the protein quality control system.In this study,we aimed to investigate the neuroprotective effect of overexpressed CHIP on Alzheimer’s disease.We used an adeno-associated virus vector that can cross the blood-brain barrier to mediate CHIP overexpression in APP/PS1 mouse brain.CHIP overexpression significantly ameliorated the performance of APP/PS1 mice in the Morris water maze and nest building tests,reduced amyloid-βplaques,and decreased the expression of both amyloid-βand phosphorylated tau.CHIP also alleviated the concentration of microglia and astrocytes around plaques.In APP/PS1 mice of a younger age,CHIP overexpression promoted an increase in ADAM10 expression and inhibitedβ-site APP cleaving enzyme 1,insulin degrading enzyme,and neprilysin expression.Levels of HSP70 and HSP40,which have functional relevance to CHIP,were also increased.Single nuclei transcriptome sequencing in the hippocampus of CHIP overexpressed mice showed that the lysosomal pathway and oligodendrocyte-related biological processes were up-regulated,which may also reflect a potential mechanism for the neuroprotective effect of CHIP.Our research shows that CHIP effectively reduces the behavior and pathological manifestations of APP/PS1 mice.Indeed,overexpression of CHIP could be a beneficial approach for the treatment of Alzheimer’s disease.

The cloning of 3'-truncated preS/S gene from HBV genomic DNA and its expression in transgenic mice

INTRODUCTIONHepatitis B virus (HBV) is regarded as one of themain etiologic factors involved in the developmentof human hepatocellular carcinoma (HCC).The open reading frame (orf)of X gene of HBVencoded a transactivating factor is the evidence thatstrongly supported the notion that the X gene ofHBV DNA integrated in HCC genomic DNA couldcontribute to the carcinogenesis of liver cells byactivation of some related cellular genes

Protective Effects of Overexpression of bcl-xl Gene on Local Cerebral Infarction in Transgenic Mice Undergoing Permanent Occlusion of Middle Cerebral Artery

In order to investigate the protective effects of the overexpression of bcl-xl gene on local cerebral infarction in the transgenic mice subject to permanent occlusion of middle cerebral artery, the models of bcl-xl transgenic mice were established and subjected to cerebral infarction by intraluminal occlusion of the middle cerebral artery. The infarct volume and the neurological scores were observed and comparison between the wild type mice and the transgenic mice was made. It was found that the infarct volume and the neurological scores in the transgenic mice were significantly decreased as compared with those in the wild type mice. It was suggested that the overexpression of bcl-xl gene in transgenic mice could reduce the infarct volume and improve the neurological function of the mice.

Generation and expression analysis of BAC humanized mice carrying HLA-DP401 haplotype

Background:Human leukocyte antigen(HLA)-DP is much less studied than other HLA class Ⅱ antigens,that is,HLA-DR and HLA-DQ,etc.However,the accumulating data have suggested the important roles of DP-restricted responses in the context of cancer,allergy,and infectious disease.Lack of animal models expressing these genes as authentic cis-haplotypes blocks our understanding for the role of HLA-DP haplotypes in immunity.Methods:To explore the potential cis-acting control elements involved in the tran-scriptional regulation of the HLA-DPA1/DPB1 gene,we performed the expression analysis using bacterial artificial chromosome(BAC)-based transgenic humanized mice in the C57BL/6 background,which carried the entire HLA-DP401 gene locus.We further developed a mouse model of Staphylococcus aureus pneumonia in HLA-DP401 humanized transgenic mice,and performed the analysis on the expres-sion pattern of HLA-DP401 and immunological responses in the model.Results:In this study,we screened and identified a BAC clone spanning the entire HLA-DP gene locus.DNA from this clone was analyzed for integrity by pulsed-field gel electrophoresis and then microinjected into fertilized mouse oocytes to produce transgenic founder animals.Nine sets of PCR primers for regional markers with an average distance of 15 kb between each primer were used to confirm the integrity of the transgene in the five transgenic lines carrying the HLA-DPA1/DPB1 gene.Transgene copy numbers were determined by real-time PCR analysis.HLA-DP401 gene expression was analyzed at the mRNA and protein level.Although infection with S aureus Newman did not alter the percentage of immune cells in the spleen and thymus from the HLA-DP401-H2-Aβ1 humanized mice.Increased expression of HLA-DP401 was observed in the thymus of the humanized mice infected by S aureus.Conclusions:We generated several BAC transgenic mice,and analyzed the expres-sion of HLA-DPA1/DPB1 in those mice.A model of S aureus-induced pneumonia in the HLA-DP401-H2-Aβ1^(-/-)humanized mice was further developed,and S aureus in-fection upregulated the HLA-DP401 expression in thymus of those humanized mice.These findings demonstrate the potential of those HLA-DPA1/DPB1 transgenic humanized mice for developing animal models of infectious diseases and MHC-associated immunological diseases.

Gene expression profile analyses of mice livers injured by Leigongteng

AIM: To analyze the gene expression profiles of mice livers injured by Leigongteng and explore the relationship between the differentially expressed genes and liver damage. METHODS: The experimental mice were randomly divided into a control group and a liver-injured group in which the mice were administrated 33 μg of triptolide/ kg per day for 30 d. Liver mRNAs were extracted from animals in both groups and were reverse-transcribed to cDNA with dUTP labeled by different fluorescence (Cy3,Cy5) as hybridization probes. The mixed probes were hybridized with oligonucleotide microarray chips. The fluorescent signal results were acquired by scanner and analyzed with software. RESULTS: Among the 35 852 target genes,29 genes were found to be significantly differentially expressed,with 20 genes up-regulated and 9 genes down-regulated. The reliability of the differentially expressed genes was validated by RT-PCR experiments of 5 randomly selected differentially expressed genes. CONCLUSION: Based on the biological functions of the differentially expressed genes,it is obvious that the occurrence and development of liver damage induced by Leigongteng in mice are highly associated with immune response,metabolism,apoptosis and the cell skeleton of liver cells. This might be important for elucidating the regulatory network of gene expression associated with liver damage and it may also be important for discovering the pathogenic mechanisms of liver damage induced by Leigongteng.

Impact of p27mt gene on transplantation model of human colorectal cancer in nude mice

AIM:To investigate the inhibitory and anti-metastatic effect of mutant p27 gene(p27mt) on the growth of colorectal cancer xenografts in nude mice and its underlying mechanism.METHODS:Inhibitory effect of p27mt gene on the growth of colorectal cancer xenografts was determined by measurement of tumor size before and after direct intratumoral injection of Ad-p27mt in a preestablished transplantation model of human colorectal cancer in nude mice.Cell cycle and apoptosis were detected by flow cytometry performed on single-cell suspension from an isolated tumor.Expression of MMP-9 in tumor tissue was detected by immunohistochemistry.RESULTS:The average sizes of transplantation tumors were 1.94 ± 0.67 cm3,2.75 ± 0.83 cm3 and 3.01 ± 0.76 cm3 in the Ad-p27mt,Ad-LacZ and control groups,respectively(P < 0.05).The average proliferation rates were 37.34% ± 1.45%,53.16% ± 3.27% and 54.48% ± 2.43%,in the Ad-p27mt,Ad-LacZ and control groups,respectively(P < 0.05).The average apoptosis rates were 19.79% ± 3.32%,6.38% ± 4.91% and 7.25% ± 5.20% in the Ad-p27mt,Ad-LacZ and control groups,respectively(P < 0.01).The average MMP-9 expression rates were 20%,75% and 66.7% in the Ad-p27mt,Ad-LacZ and control groups,respectively(P < 0.01).CONCLUSION:p27mt inhibits the growth of transplanted tumor by blocking the proliferation of cancer xenografts and by promoting apoptosis of transplantated tumor cells,as well as decrease transpl-anted tumor metastasis.

Combined probiotic bacteria promotes intestinal epithelial barrier function in interleukin-10-gene-deficient mice

AIM:To investigate the protective effects of combinations of probiotic(Bifico)on interleukin(IL)-10-genedeficient(IL-10 KO)mice and Caco-2 cell monolayers.METHODS:IL-10 KO mice were used to assess the benefits of Bifico in vivo.IL-10 KO and control mice received approximately 1.5×108 cfu/d of Bifico for 4 wk.Colons were then removed and analyzed for epithelial barrier function by Ussing Chamber,while an ELISA was used to evaluate proinflammatory cytokines.The colon epithelial cell line,Caco-2,was used to test the benefit of Bifico in vitro.Enteroinvasive Escherichia coli(EIEC)and the probiotic mixture Bifico,or single probiotic strains,were applied to cultured Caco-2 monolayers.Barrier function was determined by measuring transepithelial electrical resistance and tight junction protein expression.RESULTS:Treatment of IL-10 KO mice with Bifico partially restored body weight,colon length,and epithelial barrier integrity to wild-type levels.In addition,IL-10 KO mice receiving Bifico treatment had reduced mucosal secretion of tumor necrosis factor-αand interferon-γ,and attenuated colonic disease.Moreover,treatment of Caco-2 monolayers with Bifico or singlestrain probiotics in vitro inhibited EIEC invasion and reduced the secretion of proinflammatory cytokines.CONCLUSION:Bifico reduced colon inflammation in IL-10 KO mice,and promoted and improved epithelialbarrier function,enhanced resistance to EIEC invasion,and decreased proinflammatory cytokine secretion.

The Alzheimer's disease-associated gene TREML2 modulates inflammation by regulating microglia polarization and NLRP3 inflammasome activation

Triggering receptor expressed on myeloid cells-like 2(TREML2)is a newly identified susceptibility gene for Alzheimer's disease(AD).It encodes a microglial inflammation-associated receptor.To date,the potential role of mic roglial TREML2 in neuroinflammation in the context of AD remains unclear.In this study,APP/PS1 mice were used to investigate the dynamic changes of TREML2 levels in brain during AD progression.In addition,lipopolysaccharide(LPS)stimulation of primary microglia as well as a lentivirus-mediated TREML2 overexpression and knockdown were employed to explore the role of TREML2 in neuroinflammation in the context of AD.Our res ults show that TREML2 levels gradually increased in the brains of AP P/PS1 mice during disease progression.LPS stimulation of primary microglia led to the release of inflammato ry cytokines including interleukin-1β,inte rleukin-6,and tumor necrosis factor-a in the culture medium.The LPS-induced mic roglial release of inflammatory cytokines was enhanced by TREML2 overexpression and was attenuated by TREML2 knoc kdown.LPS increased the levels of mic roglial M1-type polarization marker inducible nitric oxide synthase.This effect was enhanced by TREML2 overexpression and ameliorated by TREML2 knockdown.Furthermore,the levels of microglial M2-type polarization markers CD206 and ARG1 in the primary microglia were reduced by TREML2 overexpression and elevated by TREML2 knockdown.LPS stimulation increased the levels of NLRP3 in primary microglia.The LPS-induced increase in NLRP3 was further elevated by TREML2 overexpression and alleviated by TREML2 knockdown.In summary,this study provides the first evidence that TREML2 modulates inflammation by regulating microglial polarization and NLRP3 inflammasome activation.These findings reveal the mechanisms by which TREML2 regulates microglial inflammation and suggest that TREML2 inhibition may represent a novel therapeutic strategy for AD.

Antiviral effects of hepatitis B virus S gene-specific anti-gene locked nucleic acid in transgenic mice

AIM To assess the antiviral effects of hepatitis B virus(HBV) S gene-specific anti-gene locked nucleic acid(LNA) in transgenic mice.METHODS Thirty HBV transgenic mice were acclimatized to laboratory conditions and positive for serum HBV surface antigen(HBs Ag) and HBV DNA, were randomly divided into 5 groups(n = 7), including negative control(blank control, unrelated sequence control), positive control(lamivudine, anti-sense-LNA), and anti-gene-LNA experimental group. LNA was injected into transgenic mice by tail vein while lamivudine was administeredby gavage. Serum HBV DNA and HBs Ag levels were determined by fluorescence-based PCR and enzymelinked immune sorbent assay, respectively. HBV S gene expression amounts were assessed by reverse transcription polymerase chain reaction. Positive rates of HBsA g in liver cells were evaluated immunohistochemistry.RESULTS Average rate reductions of HBs Ag after treatment on the 3 rd, 5 th, and 7 th days were 32.34%, 45.96%, and 59.15%, respectively. The inhibitory effect of antigene-LNA on serum HBs Ag peaked on day 7, with statistically significant differences compared with pretreatment(0.96 ± 0.18 vs 2.35 ± 0.33, P < 0.05) and control values(P < 0.05 for all). Average reduction rates of HBV DNA on the 3 rd, 5 th, and 7 th days were 38.55%, 50.95%, and 62.26%, respectively. This inhibitory effect peaked on the 7 th day after treatment with anti-gene-LNA, with statistically significant differences compared with pre-treatment(4.17 ± 1.29 vs 11.05 ± 1.25, P < 0.05) and control values(P < 0.05 for all). The mR NA levels of the HBV S gene(P < 0.05 for all) and rates of HBsA g positive liver cells(P < 0.05 for all) were significantly reduced compared with the control groups. Liver and kidney function, and histology showed no abnormalities. CONCLUSION Anti-gene-LNA targeting the S gene of HBV displays strong inhibitory effects on HBV in transgenic mice, providing theoretical and experimental bases for gene therapy in HBV.

Gene expression and cellular localizations of tumor necrosis factor-α at the site of implanted bovine cancellous bone in mice

The objective of this study was to determine if mRNA encoding for tumor necrosls factor-α(TNFα) was present at the site of implanted bovine cancellous bone and to observe the cellular localizations. The particles of bovine cancellous bone treated by special chemical reagents were implanted in the mouse’s muscle pouch. removed 5.10 and 20 days after implantation, and the specimens were processed for determining the expression and cellular localizations of TNFα mRNA, which was performed by a nonradioactive in situ hybridization technique. The results showed that (1) 5, 10 and 20 days after transplantation, the TNFα mRNA expressions were positive, andthe positive rate of expression was the highest by 10 days (P<0. 05 ). (2)There was strong hybridization signal localization to the nuclei of morphologically ldentifiable monocytes and multinucleated giant cells. (3)Similar activity was detected in the cytoplasm and (or) nuclei of partial adjacent mesenchymal cells, fibroblasts as well as striated muscle fibers. This finding tended to indicate that mRNA encoding for TNFα was intensely expressed in several kinds of cells and that TNFα seemed to be of importance for the modulation of local cellular immunity in the region of implanted xenogeneic bone.

Production of Transgenic Mice by Type-A Spermatogonia-Mediated Gene Transfer

Type-A spermatogonia first appear at between 3-7 d postnatally in mice and are the only immortalized diploid cells that reproduce in adulthood in these animals. In our current study, we explored the feasibility of producing stable transgenic mice using these cells. Enhanced pEGFP-N1 plasmids were suspended in ExGen500 transfection reagent and injected at different angles into the testes of 7-d-old male ICR mice. The resulting type-A spermatogonia-mediated gene transfer （TASMGT） mice were then mated with normal females at different stages of sexual maturity （6, 12, and 24 wk）. The integration and expression of the introduced EGFP gene was evaluated in the F1 transgenic offspring by PCR and Southern blotting analysis. The foreign gene integration rates for a low-dose group （15 μL gene suspension injected into each testis） and a high-dose group （30 μL suspensions injected） at the three stages of female sexual maturity tested were 11.76% （2/17）, 14.29% （3/21）, and 11.11% （2/18）, and 5% （1/20）, 5.56% （1/18）, and 0 （0/17）, respectively. The average integration rates for these two dose groups were 12.5% （7/56） and 3.64% （2/55）, respectively, which was a significant difference （P0.05）. Semi-quantitative RT-PCR analysis further showed that the introduced GFP gene was expressed in 3/9 integration mice. In addition, GFP expression was observed in the sperm cells from the TASMGT mice, and also in the embryos and F2 pups from the F1 generation transgenic mice. Hence, although the foreign gene integration rate for TASMGT is not high and the transgenic offspring show as yet unexplained defects, our results indicate that this method is a potentially feasible and reproducible new approach to creating transgenic mice.

Ultraviolet-attenuated cercariae ofSchistosoma japonicum fail to effectively induce a Th1 response in spite of up-regulating expression of cytotoxicity-related genes in C57BL/6 mice

Objective： To better understand the reason that Schistosoma japonicurn （S. japonicum） ultraviolet （UV）- radiated cercariae could not induce high level of protection in C57BL/6 mice. Methods： Microarray technology was performed to investigate the gene transcription profile in skin draining lymph nodes （sdLNs） at 1 w after exposure to attenuated cercariae （AC） or normal cercariae （NC） of S. japonicum in C57BL/6 mice. The expressions of some representative genes were further confirmed by real-time PCR. Subsequently, the expressions of Th1/Th2 cytokine genes, cytotoxicity-related genes, as well as co-stimulator genes in spleens from AC-vaccinated and NC- infected mice were analyzed by real-time PCR at w 3 and 6 post-exposure. Results： The gene expressions of Th1 cytokines, including interferon-y （IFN-γ）, interleukin （IL）-12 and tumor necrosis factor-α （TNF-α） in the sdLNs were significantly lower in AC-vaccinated mice than in NC-infected mice. Furthermore, the gene expressions of Th1- and Th2- cytokines, including IFN-γ, IL-12, TNF-α, IL-4 and IL-10, in the spleens from AC-vaccinated mice showed little changes at w 3 and 6 post-vaccination. In addition, cytotoxicity-related molecules including granzyme A, granzyme B, granzyme K, perforin 1 and Fas L were up-regulated from the early stage of vaccination, and peaked at the 3rd w after vaccination with UV-AC. Conclusion： UV-AC of S. japonicum could not ef- fectively induce a Thl response in C57BL/6 mice, which may be an explanation for the low protection against parasite challenge, and the role played by up-regulated expression of cytotoxicity-related genes in mice needs to be further investigated.

Differentially expressed genes in hepatocellular carcinoma induced by woodchuck hepatitis B virus in mice

INTRODUCTIONHepatocellular carcinoma(HCC)is one of the major causes of death in the word.The mechanism of carcinogenesis is unknown,although it is widely accepted that HBV and HCV are clsely related to liver cancer[1-5[1-5].Previously,a variety of studies have described the differences in gene expression which distinguished tumor from nontumor[6-11].Cloning of the genes,especially the genes associated with HBV and HCV,is still very important to account for the development of liver cancer.

<i>Lef</i>1 may contribute to agenesis of the third molars in mice

Tooth agenesis is the most common developmental anomaly of the human dentition. Epilepsy-like disorder (EL) mice, which have a 100% incidence of agenesis of the third molars, may be a good model for the genetic study of human tooth agenesis. Our previous congenic breeding strategy using EL mice confined a major locus for agenesis of M3, designated am3, within an approximately 1 Mega base pair (Mbp) interval on chromosome 3, which contains five known genes;Lef1, Hadh, Cyp2u1, Sgms2 and Papss1. The aim of this study was to identify the strongest candidate for am3 among the five genes using real-time PCR analysis. The tooth germs of M3 in the bud stage of EL and control mice were dissected out, and total RNA was extracted. In real-time PCR analysis, a significantly low level of expression of Lef1, which is one of the essential transcription factors for early tooth development, was observed in M3 of EL mice. In addition, a significantly low level of expression of Fgf4, which is a direct transcriptional target for LEF1 in early tooth development, was observed in M3 of EL mice. Our results suggest that the cause of M3 agenesis of EL mice may be a low level of Lef1 expression in M3 in the bud stage of EL mice.

EFFECTS OF PSEUDOFYPE RETROVIRUS CONTAINING HUMAN N-RAS ANTISENSE GENE ON THE GROWTH OF HUMAN LIVER CANCER LTNM4 TRANSPLANTED IN NUDE MICE

An amphotropic pseudotype retrovirus containing human N-ras antisense gene was constructed and packaged with helper cells. It has been previously demonstrated that the virus did inhibit the growth of human hepatocarcinoma cell line PLC PRF/5 in vitro accompanied with the blockage of p21 expression. Based on these results, further study was carried on to examine the effect of these viruses on the growth of human hepatoma transplanted LTNM4 in nude mice. It has been shown that the retrovirus containing human antisense N-ras gene could inhibit the hepatoma in nude mice at a rate of 78% (P<0.05) as compared with saline control. No inhibition was observed in group treated with retrovirus which contained no N-ras sequence. These results in vivo lend further support that human N-ras antisense gene mediated by retrovirus could block the expression of the relevant oncogene and lead to the inhibition of cancer growth. It also provided the basis for further approaches of gene therapy for human cancer.

Can overexpression of TGF-β1 gene change the sex ratio in transgenic mice?

Mouse TGF-β1 gene was microinjected into male pronuclei of F2 hybrid fertilized eggs obtained by mating CSJLF1 and C57BL/6J inbred strains to generate transgenic mice with over-expressed TGF-β1 gene. The rate of founder production is 31% and Southern blot analysis of founder mice tail DNAS gave an integration efficiency of 33%. TGF-β1 gene could be stably integrated to the chromosomes of transgenic mice and transmitted to their progeny at a rate of 33% in the second generation. Dot blot analysis of tail RNA of some transgenic mice indicated a moderate expression of the transgene. The most interesting finding of the present work is the striking deviation from the normal male:female sex ratio in transgenic mice,with an average ratio of 6.7:1. The possible nature of the predominance of male sex in transgenic mice overexpressing TGF-β1 is discussed.